the two presidential nominees have spent hours learning lines and performing mock debates in order to beat their opponent and win over a television audience of tens of millions. critics will be watching as we move and listening to every move. what can they learn from their predecessors? the first television debate was in black and white in 1960. it was argued that john f. kennedy had shown richard nixon mainly because of the way he looked on screen. do these debates boil down to style over substance? we're joined by brian callahan who coaches government and industry leaders in public speaking. how much do looks matter in this? if nixon had sweated less in that clip that we just saw, would he have done better? >> i think he would have. particularly since it was the dawn of television and people were getting visual cues for the first time. when senator kennedy looked much more comfortable than nixon, that played very much to his advantage. >> well, let's take a look at the presidential debate now in 1984. ronald reagan was asked if he was too old to be president. >> i want you to know t